Self-propelled bore traversing device



May 30, 1967 A. R. GAGNE 3,322,394

SELFPROPELLED BORE TRAVERSING DEVICE Filed Oct. 4, 1965 2 Sheets-Sheet l INVENTOR ARCHIE R. GAGNE i I All I w Q m Q o. m 9

ATTORNEY A. R. GAGNE 3,322,394 SELF-PROPELLED BORE TRAVERSING DEVICE 2 Sheets-Sheet 2 INVENTOR ARCHIE R. GAGNE M Aj ATTORNEY May 3U, 1967 Filed oct. 4, 1965 United States Parent 3,322,394 SELF-PROPELLED BRE TRAVERSING DEVICE Archie R. Gagne, Naperville, ill., assignor to Chicago Pneumatic Tool Co., New York, N.Y., a corporation of New Jersey Filed Oct. 4, 1965', Ser. No. 492,392 7 Claims. (Cl. 2541-4345) This :invention relates generally to devices capable of being self propelled through the `bore of a cable conduit for the purpose of introducing and laying a length of cable therein.

More recent practices in telephony require that the cables be buried underground and encased in prelaid concrete conduit, of a kind as may be shown in Gagne Pat. No. 3,185,490, issued May 25, 1965, for Reinforced Gasket for Bell and Spigot Concrete Conduit. The conduit shown in that patent is laid in end to end fashion between cable vaults, which may be up to 1000 apart. After the construction of the vaults and the conduit, the cable is laid in one or more bores of the conduit. The cable is payed from a large cable reel and pulled through a bore, to extend from vault to vault, by a winch cable secured to the telephone cable and pulled by a winch located on the ground at a cable vault spaced from the vault where the cable reel is stationed.

It is to the problem of pulling and placing a tag line in the bore prior to securing the same to a winch cable that this invention is particularly directed.

Sometimes in the construction of the concrete conduit, one or more bores thereof may become filled with unwanted debris which would prevent the ready placement of the cable in the bore. The structure according to the present invention finds use in locating an obstruction, and if the obstruction is so large as to prevent movement therepast, the structure is capable of backing readily out of the bore. The location of the obstruction can be noted by the amount of the supply hose for motive fluid payed out. The position of the obstruction being noted, the backiill over the conduit can be removed, the conduit inspected, and the obstruction removed.

The structure according to the invention also finds particular use in placing a strand of wire or cable in the bore for the purpose of thereafter securing a swab or other cleaning device to the Wire and cleaning the bore of sediment or the like.

With the foregoing considerations in mind it is a principal object of the invention to provide an improved self propelled device for introducing a cable or wire into the bore of prelaid conduit.

Yet another object is to provide a device of a general character to be described, but capable of reversal if the device encounters an obstruction in the bore.

A still further object comprehends the provision of a self propelled structure powered by motive fluid furnished by a supply hose, and to cause the device to move with a small -cable in the bore, the device being separable from the supply hose and the small cable when it reaches the end of the bore, the small cable being adapted to be connected to a heavier cable and then withdrawn from the bore and separated from the heavier cable, the latter being attached at one end to the heavy telephone cable, and at the other end to a winch for pulling the telephone cable through the bore.

Other objects and important features of the invention will be apparent from a study of the specification following taken with the drawings which together describe and illustrate a preferred embodiment of the invention and what is now considered to be the best mode of practising the principles thereof. Other embodiments may be sugn gested to those having the beneiit of the teachings herein,

3,322,394 Patented May 30, 1967 and such other embodiments are intended to be reserved especially as they fall within the scope of the subjoined claims.

In the drawings:

FIG. 1 is a longitudinal sectional view th-rough a trench laid concrete conduit having the structure according to the present invention shown situate in one of the bores thereof;

PIG. 2 is a longitudinal section showing the concrete conduit extending between two `spaced apart cable vaults;

FIG. 3 is a longitudinal sectional view of the selfpropelled bore traversing device according to the present invention, certain parts thereof being shown in elevation;

FIG. 4 is a transverse sectional View taken along the line 4-4 of FIG. 3 looking in the direction of the arrows;

FIG. 5 is an elevational view of a resilient fingered disc adapted to engage the walls of the bore in which the device of FIG. 3 is adapted to traverse; and

FIG. 6 is a side View thereof.

Referring now particularly to FIGS. 1 and 2 of the drawings the self-propelled bore traversing device according to the present invention is referred to generally by the reference numeral 10, and is shown in its site of operation in connected lengths of concrete conduit 11 such as is shown in the already referred to Gagne patent. The conduit has a plurality of cylindrical bores 12 therein which are traversed by the device 10 for performing the preliminary steps necessary to the pulling or snaking of telephone cable in the bore. As seen in FIG. 1 the conduit sections 11 have a rectangular cross section and are provided with a rectangular shaped bell 13 into which a spigot 14 of an adjoining section is fitted, a tight joint being made between the bell 13 and spigot 14 by means of a gasket 16 as shown in the aforementioned Gagne patent.

Referring now to FIG. 2 of the drawings the connected lengths of conduit 11 are laid in a trench below the ground surface GS, and the conduit lengths 11 extend between spaced cable vaults CVI and CVZ. The device 10 is adapted to advance from one vault to the other in a bore 12 of the -conduit 11, the device being powered by a supply hose 17 which is secured to the trailing end thereof. Preferably, the device 10 has also secu-red thereto a small airplane type retrieving cable 18, approximately 1/16 O.D. and capable of sustaining a pull of from 900 to 1000 pounds. The device 10 is self propelled by motive iiuid supplied by the supply hose 17, and moves from vault CV2 to vault CVil for example, in a series of repeated movements wherein a front abutment member 19 of device 10 engages the wall of the bore 12 and pulls the device 10 towards itself, while a rear abutment member 21 moves toward the front abutment 19. This movement is accompanied by trailing movement of the supply hose 17 and the retriever cable 18.

As a part of the repeated movements of the device 10, and after the aforesaid movement has been completed, the rear abutment member 21 engages the sides of the bore 12 whilst the front abutment member moves with -respect to the device 10 to take a purchase upon the walls of the bore to repeat the aforesaid operations until the device has moved from one end of the bore 12 to the other.

The motive fluid for the bore traversing device 10 is supplied from a vehicle 22 having wheels 23, and includes a prime mover 24 driving an air compressor 26 supplying air under pressure to device 10. The two cables 17 and 1S are payed from a winch 27 which can be driven in a return direction by the prime mover 24, the latter being connected to a winch 27 by a drive belt 28, and to the air compressor 26 by a drive belt 29.

Oftentimes all the bores 12 are not occupied by the cables, but future needs malte it desirable to place a tag line in a bore, so that some time in the future a cable may readily be laid therein. Such tag line can in the future be connected to a winch cable, and the tag line withdrawn from the bore with the winch cable left in the bore. When the tag line is disconnected from the winch cable, the latter is connected to the communication or power cable, so that the latter can be placed in the bore.

In some instances, one or more of the bores will have the power or communications cable placed immediately therein, and the device according to the invention can be separated from its supply hose and retriever cable, and the winch cable connected to the retriever cable, both the retriever cable and the supply hose being then rewound upon the winch 27.

Either method or a combination of the two methods may be employed as the exigencies demand.

As an example, when it is merely desired to place a tag line in the bore 12, the following operations will take place. When the bore traversing device reaches the end of the bore 12 it is disconnected from the supply hose 17 and the retriever cable 18, this latter cable being then secured in any convenient manner to a tag line 31 stored on a supply reel 32 mounted on a vehicle 33 having ground engaging wheels 34. The tag line 31 may be of nylon or similar material, or No. 9 wire, capable of sustaining pulls of the order of 1000 lbs. After being connected to the tag line 31 retriever cable 18 together with supply hose 17 is wound upon the winch drum 27, to be stored thereon for subsequent use. Tag line 31 is left in the bore 12 for future use.

At such future time tag line 31 can be connected to a `winch cable WC wound upon a winch 36 mounted on a winch truck 37 having ground engaging wheels 38. The other end of tagline 31 is connected to a small winch, not shown, at cable vault CV2, and winch cable WC is pulled by tag line 31 the full length of bore 12. Tag line 31 is then disconnected from winch cable WC, and the latter is then connected in any convenient fashion to a communications -or power cable TC. Cable TC is stored upon a supply reel SR mounted on a wheeled vehicle 42 or any other suitable device.

If it is desired to place the cable TC immediately after the bore traversing tool 10 reaches the end of a bore 12 at cable vault CV1, tool 10 is disconnected from supply hose 17 and retriever cable 18. The latter is then connected to the winch cable WC, and supply hose 17 and retriever cable 18 wound upon winch 27. Winch cable WC, after being laid in the bore 12 is then connected to cable TC. Winch cable WC is then wound upon cable winch 36, and bore 12 laid with cable TC.

The aforesaid operations can be continued until each of the bores 12 is strung wth a tag line 31 or cable TC.

The details of the bore traversing tool 10 are best seen with respect to FIGS. 3 to 6. Tool 10 comprises the first or rear abutment member 21 secured between a rear manifold member 46 and a pressure collar 47 by a fastening nut 48 threaded to a nipple 49 tapped into the rear manifold member 46. Air hose 17 is secured in any convenient fashion to nipple 49, and the retriever cable 18 is secured to an eye 51 extending from the pressure collar 47. As seen in FIGS. 5 and 6, the rear abutment member 21 has a number of equiangularly spaced resilient lingers 52 having leading faired surfaces 53, which surfaces intersect back wall 54 of abutment member to present a plurality of edges 56 adapted to engage the walls of the bore 12.

A porting assembly consisting of an outer porting sleeve 57 and a pair of nested porting sleeves 58 and 59 concentric with outer porting sleeve 57 are adapted to direct the movement of motive fluid within the device 10, and to control the movement of the second abutment member 19 with respect to the device 10 to move the same in the bore 12. Innermost porting sleeve 59 is held by a pair of llat head screws 61 to porting sleeve 58, and

porting sleeve 58 is in turn threaded at 62 to the rear manifold member 46. Innermost porting sleeve 59 is properly spaced from the manifolding member 46 by a locating sleeve 63.

Porting sleeve 58 is coaxial with a cylinder sleeve 64, also nested in outer porting sleeve 57, and is coupled to cylinder sleeve 64 by a coupler 66 having an annular flange 67. One end of porting sleeve 58 abuts annular flange 67 and one end of the cylinder sleeve 64 abuts the other side of flange 67 of coupler 66. The latter is held to the porting sleeve 58 and to the cylinder sleeve 64 by means of respective snap rings 68 and 69. Suitable openings, not shown, in porting sleeve 58 and cylinder sleeve 64 are provided to engage the ends of snap rings 68 and 69 for collapsing the same, and disconnecting the coupler 66 from the sleeves 58 and 64.

The outer porting sleeve 57 is supported upon porting sleeve 58 and cylinder sleeve 64 and is held thereon be tween the rear manifold member 46 and a front closure disc 73 threaded at 74 to a front manifold member 76. The latter is held by a snap ring 77 to the cylinder sleeve 64, and cylinder sleeve 64 may have radial openings, not shown, for engagement of the ends of snap ring 77 to collapse the same for disassembly of manifold memd ber 76 from cylinder sleeve 64.

As seen in FIG. 4, porting sleeve 57 has a plurality of drilled passageways extending longitudinally of the same. These passageways are arranged in -diametrically spaced pairs and include pressure passageways 78, 78 connected to a manifold passageway 79 in rear manifold member 46. Manifold passageway 79 is in turn connected at nipple 49 in turn connected to supply hose 17. Pressure passageways 78, 78 are intersected by radial pasd sageways 81 in porting sleeves 57, 58 and 59.

As seen in FIG. 3, the motive uid at pressure passageways 81 moves past an annular groove 82 of a hollow spool valve member 83, past radial passageways 84 in porting sleeves 57, 58 and 59 to longitudinal passaged ways 86 to be directed into a passageway 87 in front manifold member 76.

A piston rod 88 is slidable in front manifold member 76 and supports at the front end thereof the front abutment member 19. The latter is identical in construction to rear abutment member 21 seen in detail in FIGS. 5 and 6, and is held between spaced discs 89 and 91, and is secured by a cap screw 92 tapped into the front end of piston rod 88.

A piston indicated generally by reference numeral 94 is supported on piston rod 88 and bears against a shoulder 96 thereon. Piston 94 is held in position by and between a retainer nut threaded onto a portion 96, which is tapped at 97 into piston rod 88.

Piston rod 88 has a lost motion connection with valve spool 83, which has a bore 97 therein to receive a head 98 of a valve spool actuating bolt 99. The inside end of piston rod 88 is tapped at 101 to receive the threaded end of bolt 99, and the same is locked in position by a lock nut 102.

The pressure iluid at front manifold member 87 moves piston 94 and piston rod 88 relative to the device 10. At this time front abutment member 19 is locked in bore 12 by its fingers 53, and rear abutment member 21 trails with outer porting sleeve 57.

As actuating bolt 99 moves to the left with respect to valve spool 83 no motion of the latter takes place until bolt head 98 strikes an abutment 103 threaded into the bore 97 of hollow valve spool 83. The continued movement of piston 94, piston rod 88 and actuating bolt 99 causes the valve spool 83 to be picked up until abutment 103 strikes rear manifold member 46.

During the aforesaid movement of piston 94, and prior to movement of valve spool 83, volume 104 in front of piston 94 is swept thereby, and spent motive fluid is vented past an end land 106 of spool 83, a land 107 on innermost porting sleeve 59 to exhaust by way of radial exhaust ports 108 in the porting sleeves 57, 58 and 59.

During the movement of piston 94, and prior to valve spool 83 being moved, an end land 109 on valve spool 83 laps ports 111 in porting sleeves 58 and 59. Ports 111 are connected to longitudinal passageways 112 in outer porting sleeve 57. Radial passageways 113 connect longitudinal passageways 112 with the volume 104 in front of piston 94.

It will be seen that spent motive uid in front of the piston 94 to be exhausted from the device 10 only by the passageway 108.

At the conclusion of the aforesaid described movement of piston 94 with respect to the porting sleeves 57, 58 and 59, the device is ready for a movement whereby the rear abutment 21 will be engaged in the bore 12 while the forward abutment member 19 is thrust forward in the bore 12 and with respect to the device 10. It will be remembered that during the movement previously described, front abutment 19 is engaged in bore 12 while rear abutment 21 moves toward front abutment 19. The supply hose 17 and retriever cable 18 (the latter being engaged at eye 51) are dragged along in the bore 12.

The yaction of the piston rod 96 and bolt 99 in picking up valve spool 83 causes motive fluid to be directed against the left side of piston 94 as seen in FIG. 3 to move front abutment 19 in bore 12.

At this time, when valve spool 831 is moved completely to the left, pressure fluid will move from pressure port 81 past groove 82 on spool 83 to ports 111 and passageway 112. The pressure fiuid moves into volume 104 by way of passageway 113 against piston 94 to urge it and front abutment 19 to the right.

Spent fluid is exhausted from the other side of piston 94 by a path consisting of passageway 87 in front manifold member 76, passageway 86 in outer porting sleeve 57, passageway 84, a groove 114 between a land 116 and end land 106 on spool 83, the spent fluid being then eX- hausted by way of radial exhaust ports 108. It should be noted that during this time end land 106 of spool 83 laps land 107 on innermost porting sleeve 59.

Piston 94 together with front abutment 19 advances with respect to valve spool 83 and rear abutment 21 until the lost motion between piston 94 and valve spool 83 is taken up, at which time valve spool 83 is pulled to the right until it adopts the position seen in FIG. 3l. At such time, the rst described operation takes place again.

It will be seen that the device 10 is thus adapted to be self propelled through the bore 12 by repeated cycles of movement wherein the front and rear abutments 19 and 21 alternately engage the bore. During such cycles the supply hose 17 and retriever cable 18 are carried along with the device 10.

The repeated cycles cause the device 10 to be moved to the end of the bore 12, at which time device 10 is disconnected from supply hose 17 and retriever cable 18. As was previously described, retriever cable 18 is then connected to winch cable 31, and rewound on the winch 27. Winch cable 31, being laid in bore 12 is then adapted to be connected to cable TC at cable vault CVI, and to be wound on winch 38 at cable vault CV2. Cable TC is then pulled into the bore 12.

While cable TC is being placed in a bore 12, the device 10 can be started in an adjacent bore 12. The winch cable 31 can be payed from winch 38 on to supply reel 32, which is preferably provided with means for winding cable 31 thereon.

The structure according to invention also finds use in determining the position of an obstruction in a bore 12. The winch 27 may be provided with a counter, not shown, for measuring the amount of supply hose 17 and retriever cable which have been payed out. If the device meets the obstruction, and is prevented from further forward movement, the position of the obstruction may be noted and 6 reached by digging at the ground surface GS seen in FIG. 2.

The device according to the present invention is also capable of reversing itself upon encountering an obstruction. This is done by placing a pull on the retriever cable 18. Such a pull may be of the order of two to three hundred pounds which will cause the front and rear resilient abutments 19 and 21 to be flexed in an opposite sense by overcentering. Front abutment 19 then becomes the rear abutment, and vice versa.

Consider a situation Where there is a pull on retriever cable 18 connected to eye 51, and the parts are in the position seen in FIG. 3. Pressure at supply hose 17 will be manifested against piston 94 at front manifold member 76 to move front abutment 19 to the left. When actuator bolt 99 moves spool 83 to the left, pressure is placed against the opposite side of Ipiston 94, and by reason of the pressure of the motive fluid and the pull in retriever cable 18, the device 10 moves to the left, At this time front abutment 19 is engaged with bore 12, and rear abutment 21 has its flexible ngers 53 overcentered, as described.

It will be seen that the device 10 can thus out of the bore 12 in the manner described.

The device 10 may also be employed with a swab, not shown, which trails with the supply hose 17 and retriever cable 18, to wipe the inside of the lbore 12 of fine silt, dust or the like.

From the description foregoing it is believed evident that some new and useful improvements in devices adapted to be self-propelled within a bore have been provided.

Having thus described this invention in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains to make and use the same, and having set forth the best mode contemplated of carrying out this invention, the subject matter regarded as being patentable is particularly pointed out and distinctly claimed in what is claimed, it being understood that equivalents or modifications of, or -substitutions for, parts of the above specifically described embodiment may be made without departing from the scope of the invention as set forth in what is claimed.

I claim:

1. In a device of the class described for traversing the length of -a bore in a conduit or the like, a rst abutment member having means thereon engaging the wall of said bore, a porting structure connected to said first abutment member, said porting structure having a plurality of ports therein, means connecting one of said ports to a supply of motive fluid under pressure, a valve member movable with respect to said porting structure to connect a second of said plurality of ports in said porting sleeve to said one port and said supply of motive fluid, a second abutment member having a lost motion connection with respect t0 said valve member and adapted to move with respect to said porting structure, means on said second abutment member adapted to engage the wall of said bore, means on said second abutment member adapted at times to be subject to pressure from said supply of motive uid when said valve member is in a position to connect said second port to said supply of motive fluid to move said porting structure with respect to said abutment member while the latter is stationary in said bore, said movement of said porting structure causing said lost motion connection between said second abutment member and said valve member to be taken up and cause said valve member to move to a position connecting said supply of motive Huid with a third of said plurality of ports in said porting structure to subject the pressure means on said second abutment member with pressure of a different sense to move said second abutment member in said bore with respect to said porting structure and said rst abutment member while the latter is stationary in said bore.

2. The invention according to claim 1 wherein strucback up ture is provided in said porting structure and cooperating with said valve member for connecting a side of the means on said second member to exhaust when said second port is connected to said supply of motive fluid.

3. The invention of claim 1 Where structure is provided in said porting structure for connecting the opposite side of said pressure means to exhaust when said third port is connected to said supply of motive fluid.

4. The invention of claim 1 wherein the pressure means on said second abutment member includes a piston adapted to have pressure selectively applied to opposite sides thereof by said porting structure and said valve member.

5. The invention of claim 1 wherein the pressure means ond said second abutment member includes a piston rod having said lost motion connection to said valve member and a piston mounted on said piston rod.

6. The invention according to claim 1 wherein said porting structure includes an outer sleeve having longitudinal passages therein adapted to supply motive uid to said irst port and to said pressure means on said second abutment.

7. The invention of claim 1 wherein said first abutment member is connected to a supply hose and to a retriever cable, and wherein both of said abutment members include resilient fingers adapted to engage the wall of said bore and move to an over-centered condition when a pull 5 in excess of a predetermined amount is placed on said retriever cable to cause said device to operate in an opposite direction and withdraw from said bore.

References Cited 3,224,734 12/1965 Hill 254-134-6 FOREIGN PATENTS 614,592 12/1948 Great Britain.

WILLIAM FELDMAN, Primary Examinez'. 2 OTHEL M. SIMPSON, Examiner. 

1. IN A DEVICE OF THE CLASS DESCRIBED FOR TRAVERSING THE LENGTH OF A BORE IN A CONDUIT OR THE LIKE, A FIRST ABUTMENT MEMBER HAVING MEANS THEREON ENGAGING THE WALL OF SAID BORE, A PORTING STRUCTURE CONNECTED TO SAID FIRST ABUTMENT MEMBER, SAID PORTING STRUCTURE HAVING A PLURALITY OF PORTS THEREIN, MEANS CONNECTING ONE OF SAID PORTS TO A SUPPLY OF MOTIVE FLUID UNDER PRESSURE, A VALVE MEMBER MOVABLE WITH RESPECT TO SAID PORTING STRUCTURE TO CONNECT A SECOND OF SAID PLURALITY OF PORTS IN SAID POURING SLEEVE TO SAID ONE PORT AND SAID SUPPLY OF MOTIVE FLUID, A SECOND ABUTMENT MEMBER HAVING A LOST MOTION CONNECTION WITH RESPECT TO SAID VALVE MEMBER AND ADAPTED TO MOVE WITH RESPECT TO SAID PORTING STRUCTURE, MEANS ON SAID SECOND ABUTMENT MEMBER ADAPTED TO ENGAGE THE WALL OF SAID BORE, MEANS ON SAID SECOND ABUTMENT MEMBER ADAPTED AT TIMES TO BE SUBJECT TO PRESSURE FROM SAID SUPPLY OF MOTIVE FLUID WHEN SAID VALVE MEMBER IS IN A POSITION TO CONNECT SAID SECOND PORT TO SAID SUPPLY OF MOTIVE FLUID TO MOVE SAID PORTING STRUCTURE WITH RESPECT TO SAID ABUTMENT MEMBER WHILE THE LATTER IS STATIONARY IN SAID BORE, SAID MOVEMENT OF SAID PORTING STRUCTURE CAUSING SAID LOST MOTION CONNECTION BETWEEN SAID SECOND ABUTMENT MEMBER AND SAID VALVE MEMBER TO BE TAKEN UP AND CAUSE SAID VALVE MEMBER TO MOVE TO A POSITION CONNECTING SAID SUPPLY OF MOTIVE FLUID WITH A THIRD OF SAID PLURALITY OF PORTS IN SAID PORTING STRUCTURE TO SUBJECT THE PRESSURE MEANS ON SAID SECOND ABUTMENT MEMBER WITH PRESSURE OF A DIFFERENT SENSE TO MOVE SAID SECOND ABUTMENT MEMBER IN SAID BORE WITH RESPECT TO SAID PORTING STRUCTURE AND SAID FIRST ABUTMENT MEMBER WHILE THE LATTER IS STATIONARY IN SAID BORE. 